Precipitator cleaning device



Feb. 24, 1931. c. w. .J. HEDBERG ET AL 1794,074

CLEANING DEVICE FRECIPITATOR Filed June 19, 1926 4 Sheets-Sheet l I INENTORS:

R m T A Feb. 24-, 1%!- c. w. J. HEDSERG ET AL, 1 9

PRBC;PITATOR CLEANING DEVICE Filed June 19, 1926 4 Stems-Sheet 2 I 6% a10w J0 J00 i s FLJ/E J} Feb. 24, I931.

c. w. J. HEDBERG ETAL PRECIPITATOR CLEANING DEVICE Filed June 19, 1926 4Sheets-Sheet 5 W INENTOR6E ATTORNEYS.

Feb. 24, 1931.

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c. w. J. HEDBERG ETAL -l, 794,074 f PRECIPITATOR CLEANING DEVICE iilleazi June 19, 1926 4 Sheets-Sheet 4 2 Q E ATTORNEY-S'.

Patented Feb. 24, 1933 UNITED STATES TENT OARL W. J. HEDBERG, OFMIDDLESEX BOROUGH, NEW JERSEY, AND HARRY A. WIN- T'EBMUTE, OF NEW YORK,N. Y., ASSIGNORS TO RESEARCH CORPORATION OF NEW YORK, N. Y., CORPORATIONOF NEW YORK PRECIPITA'I'OB CLEANING DEVICE Application filed June 19,

This invention relates to electrical precipitators and more inparticular to apparatus for cleaning the collecting electrodes.

The object is apparatus for uniformly removing material from plateelectrodes.

It is a particular object to provide mechanism for removing from plateelectrodes deposit which is not readily removed by ordinary means.

The'invention, the principle of operation on which it is based and theadvanta es resulting therefrom will be fully descri ed in connectionwith the accompan ing 'drawin and the points of novelty will tieparticular y defined by the claims. I

In the drawings:

Fig. 1 is a view partly in elevation and partlyin section embodying oneform of the invention;

Fig. 2 is a fragmentary section at right angle to Fig. 1;.

Fig. 3 is a fragmentar sectional view showing a modifiedform o theinvention;

Fig. 4 is a fragmentary sectional view taken at right angle to Fig. 3;

Fig. 5 is a fragmentary sectional view of another embodiment of theinvention;

Fig. 6 is a fragmentary sectional view taken at right angle to Fig. 5;

Fig. 7 is a fragmentary edge view representing still another form of theinvention;

and

Fig. 8 is a fragmentary elevation thereof.

In Fig.- 1 is shown what may be called a typical modern plate treater.For the sake of general understanding it may be stated that withinacasing 1, which has gas inlets 2 and outlets 3 is mounted upon beams 4a plurality of plates 5 in uniformly spaced relation. From a framework 6are suspended the discharge electrodes 7 disposed in the spaces providedby the plates 5 which are the collecting electrodes.

The particular mechanism for cleaning the plate electrodes 5, shown inFigs. 1 and 2, is a pair of chains 8 for each plate. These chains aresupported by a roller 9 normally resting upon the upper edge of theplate and are disposed on opposite sides of the plate, the lower endcarrying a weight 10. The ar- 1926. Serial No. 117,092.

rangement is such that the chains are tact with the plate.

To provide means for moving the cleaning units, we provide two shafts 9aabove the in conplates 5 and extending at right angles to said movedacross their respective plates by rotation of the proper shaft 912.

At the lower end of plates 5, two similar horizontal shafts we areprovided, carrying sprocket wheels 106. One sprocket wheel is providedfor each plate 5, and a continuous chain 100 is mounted upon eachsprocket, as seen in Fig. 2. Each weight 10 is connected to its resective cross-chain 100, so that all the weig ts 10, and thereby thecleaning chains 8, can be moved across the plates, 5 by rotation of theproper shaft 10a. It is thus possible to drag the cleaning chains fromabove or below the plates 5, and in some cases a more thorough cleaningma be obtained by alternately dragging from a ove and below. It issometimes desirable to move chains 8 simultaneously from above and belowand to accomplish this, it is merely necessary to connect one shaft 9awith a shaft 10a, by means of a chain drive, as seen in Figs. 1 and 2.It is obvious that other means could be used for synchronizin g the topand bottom drives, such as shafting with bevel gears thereon. It is alsoobvious that other means of drive may be used at the top and bottom,such as rack and pinion, or pneumatic piston. We do not wish to belimited to the specific structure shown, but merely show such drives forillustration only, and include within the scope of our invention allmechanical equivalents of such means.

While the treater is in operation all the cleaning units are disposed atone end of the plates out of the sphere of action of the dischargeelectrodes, as shown in Fig. 2. When the cleaning operation is to becarried out, the rollers 9 are moved along the upper edges of the platesfrom one side to the other as often as is necessary to effect therequired cleaning action. The electrical action is preferably suspendedwhile the cleaning operation is performed.

The weights 10 may be proportioned to bring about any desired pressureaction of the chains upon the plates. depending largely upon the natureof the deposit.

The arrangement shown in Figs. 3 and 4 is generally similar to thatshown in Figs. 1 and 2. However, the chains 11 are supported upon bars12 or the like above the support 12' for the discharge electrodes, asfor instance by means of rings or collars 13. This arrangement makes itpossible to move av plurality or all of the chains at the same time. Thecleaning members 11 may be moved over the electrodes 5 by links orchains attached to the collars 13. or to the chains depending therefrom,and operated by mechanism similar to that designated by numerals 9a. 9b,90, 10a, 10?), and 100 of Fig. 1, or the collars 13 may be moved alongthe rods 12 by any other suitable mechanism.

As indicated, rollers 14 may be used as before. However, there is roomfor various changes in respect to the particular arrangement.

Figs. 5 and 6 show a form of mechanism in which the discharge electrodesmay be used for cleaning the collecting electrodes. Plates 15 and 16represent a pair of collecting electrodes defining a gas duct 17. Thedischarge electrodes for this gas duet comprise two or more chains 18 orother flexible conducting carriers for the electrodes 19 proper whichare rods extending transversely of the duct.

Instead of being supported from a stationary support as is usual, wesupport each chain from a segmental element 20 in the nature of a partof a sheave mounted upon a transverse rod 21. For a two-chain supportfor the el ectr0des 19, two elements 20 are used mounted in the desiredspaced relation on the rod 21 (only one chain being shown in Fig. 6).

To operate the cleaning mechanism, the discharge electrodes are firstdisconnected from the source of current, as is bbvious. and then theshaft 21 is turned first in one direction to clean plate 15 and then inthe opposite direction to clean plate 16. By turning the shaft 21, thedischarge electrode mechanism is brought into contact with theplates andthe up-and-down movement effected by further turning the shaft 21 causesthe electrodes 19 to sweep up and down along the plate to remove thedeposit. By bodily moving the elements along the shaft in one or theother direction. the range of the cleaning action may be extended. Theshaft 21 may be angular-1y moved by the usual crank or, if

desired, any form of mechanical movement may be used, as is obvious. Theprincipal and important thing is the movement of a discharge system ofthe character disclosed, in such a way as to remove the deposit from theplates. All details that may be used in addition thereto are merematters of expediency and do not form any part of the patentablenovelty. The segmental element 20 may have a diameter substantiallyequal to the distance between the plates 15 and 16 or a little greater.

In F 7 and 8, we have shown a form of construction in which horizontalcleaning elements are moved vertically from top to bottom and arenormally kept in an inoperative position above the plates.

The plate 25 represents one of a plurality of collecting electrodes, asindicated in Fig. 1, and the discharge electrodesystem including thetransverse discharge members 26, the pendant supporting members 27 andthe support 28 is preferably the same as shown in Fig. 1, but may be ofany other construction.

The cleaning mechanism comprises a pair of rods or bars 29 supported atopposite ends by toggle joints 30, the upper ends of which are suportedon chains 31 or the like, while the lower ends carry weights 32.

At each end of the plate 25 is a vertical guide 33 of substantially thesame width as the thickness of the plateand in alignment with the plate.This guide has above the upper edge of the plate a tapering portion 34.

The operation is as follows:

Normally the mechanism is substantially in the position shown in Figs. 7and 8. The weight 32 causes the rods 29 to press against the surfaces ofthe guides which on the portion 34 are so related that the rods 29 arepreferably within the planes defined by the surfaces of the plate 25 orat least do not project beyond these planes. There is considerablelatitude in this respect, the object being to place the rods 29 out ofthe sphere of action of the discharge electrodes and more particularlyout of reach of the pendant portions 27 of the system shown.

To effect the cleaning operation, the

ichains 31 which may be wound upon sheaves or drums, are loweredthereby, allowing the rods to move downwardly along the guides 33,theweight 32 drawing the bars against the edges of the guides with a forcewith each generally proportional to the weight. The rods are thus causedto move over the surfaces of the plates or even in contact therewith,the scraping action of the rods again being a function .of the weight32. The rods may be moved up and down as often as desired to satisfy theparticular conditions, and after the cleaning operation is completed therods are moved back into the operative position above the plates.

In the foregoing we have shown various forms of cleaning devicesoperable to move over the surface of the collecting electrodes to removedeposit therefrom and normally in a position permitting the normaloperation of the treater. The forms shown are intended to merelyillustrate the general character of a larger class of devices availablefor the purposes of the invention and to particularly show some of theforms Well adapted for the practical requirements.

It is understood that instead of gravity action mechanical means may beemployed to press the cleaning elements against the plates; as forinstance springs or the like. The cleaning or scraping elements mayassume many different forms. There is practically no limit in respect tothe mechanism for imparting movement to the cleaning devices proper toeffectively cover the whole area of the plates.

We claim:

1. In an electrical precipitator, the combination with a collectorelectrode having a substantially vertical planar surface against whichseparated material collects, of means for removing deposits of materialfrom said collector electrode, said means comprising a support locatedabove said collector electrode, a flexible cleaning device suspendedfrom said support and due to gravity lying substantially in a planeparallel to the surface of said collector electrode, andmeans for movingsaid cleaning device over thesurface of said electrode.

2. In an electric precipitator of the platetreater type, the combinationwith a late electrode, of a cleaning device mounts for movement over thesurface of the plate electrode and a weight associated with said devicetending to press the same into contact with the plate electrode.

3. In an electric precipitator of the platetreater type, the combinationwith a plate electrode, of means on opposite sides of the plateelectrode, disposed to be moved as a unit over the opposite surfacesthereof, and means tending to press the said means into contact with thesurfaces.

4. In an electrical precipitator, a collecting electrode having acollectingsurface,

discharge electrode means spaced from and opposing said'collectingsurface, a cleaning device, and means for moving said cleaning devicebetween said collecting electrode and said discharge electrode means andover said collecting surface.

5. An electrical precipitator as set forth in claim 4, in which thecleaning device comprises weighted members.

6. In an electrical precipitator of the bodily and transversely betweensaid plate and said discharge electrode means and over substantially theentire area of said surface.

7. In an electrical precipitator, a collecting electrode having acollecting surface, discharge electrode means spaced from and opposingsaid collecting' surface, a cleaning device, and means for moving saidcleaning device between said collecting electrode and said dischargeelectrode means and over said collecting surface, and for also movingsaid cleaning device out of position between said collecting electrodeand said discharge electrode means.

8. In an electrical precipitator of the plate-treater type, a plateelectrode, discharge electrode means spaced from and opposing a'surfaceof said plate, a cleaning de vice extending substantially entirelyacross said surface of the plate in one direction, and means for movingsaid cleaning device bodily and transversely between said plate and saiddischarge electrode means, and over substantially the entire area ofsaid surface, and for also moving said cleaning device ont of the spacebetween said plate and said discharge electrode means.

9. In an electrical precipitator, a collecting electrode having acollecting surface, discharge electrode means spaced from and opposingsaid collecting surface, a cleaning device, means for moving saidcleaning device between said collecting electrode and' said dischargeelectrode means and over said collecting surface, and means associatedwith said cleaning device tending to press the same into contact withsaid collecting electrode.

10. In an. electricalprecipitator, a collector electrode, a dischargeelectrode, and means for moving said discharge electrode over thesurface of said collector electrode to remove de osits therefrom.

11. The invention as set forth in claim 10 wherein said collectorelectrode comprises a plurality of flexibile suspension members andhorizontal rods secured to and extending transversely of said suspensionmem bers; and said means comprises an angularly-displaceable. supportfor theupper ends of said suspension members.

In testimony whereof, we aifix our signatures.

CARL W. J. HEDBERG. HARRY A. WINTERMUTE.

plate treater type, a plate electrode, discharge electrode means spacedfrom and opposing a surface of said late, a cleaning device extendingsubstantially entirely across said surface of the plate in onedirection, and means for moving said cleaning device

